1. Field of the Invention
The invention relates to a sealing device for a gap between two adjacent machine parts, including at least one inflatable, elastically stretchable tube, which is fitted into a groove in the sidewall of one of the machine parts, and which, when inflated, may be positioned against a surface, of the other machine part, which borders the gap on the side opposite the groove.
2. Description of Related Art
Sealing devices of this kind are used, for example, in foaming tools, in which the two tool halves are of great extension. Because of that, it is difficult to close off the sealing gap between the two halves of the form, that are made of solid material, so tightly after closing that the reaction mixture that was put in in the liquid state cannot get out and pollute the environment.
A sealing device of this kind is known from DE 199 16 789 C1. The sealing tubes described there are accommodated at both ends in molded parts made of a solid material, which in their area have a sealing function with respect to the sealing gap at the same time. At least one of the filler pieces is furnished with a duct-shaped recess through which compressed air may be blown into the tube or let out of it. That is what makes it possible to bring the inflated tube, over its whole length, into engagement with the surface of the forming tool lying opposite, and to seal the sealing gap over this length. This has no influence on the immediate area of the molded part. Therefore, leakage can occur at that place. For that reason, the known sealing device is not suitable for applications in which the sealing gap has to be sealed over its entire length. For instance, for the production of complex foam members in which, even in the end regions of the sealing tubes, very precise sealing is to be achieved, a new solution is being sought.
A further disadvantage of the known solution is that the molded parts partially have to project over the surfaces of the machine parts in order to achieve sealing that is as good as possible. Thus, they often form an interference for secondary members which are inserted parallel to the surface of the machine part when the forming tool is open. This is often the case, for example, for inserts which may act to reinforce plastic foam parts to be manufactured. Thus the above molded parts in these cases impair the accessibility to the forming tool.